## Tangrams – Series I,II,III

### Introduction

The Cycle Rule and Form deals with the composition of 7 simple geometrical figures. These figures are derived from the chinese tangram by splitting a square (see also rule 24) into 7 simple figures:

- two large triangles,
- one midsize triangle,
- two small triangles,
- a square,
- a parallelogram.

### Composition principles

The rules relate geometrical properties like corners, sides and angles of the figures to each other. Symmetry properties are also employed. The notion of a chain is used intuitively, without a mathematical definition. The number of a rule shows the sequence when it was created. Series I, II and III combine similar rules.

### Series I - Surroundings (19 Rules)

The rules describe properties of the interior of a resulting figure or the figures surround an geometrical defined interior.

### Series II - Angles and Sides (23 Rules)

The rules use geometrical properties of the figures, especially corners, angles and sides. The rules describe relations between single figures.

### Series III - Symmetry and Convexity (14 Rules + 2 Variants)

The rules describe properties of the resulting figure, especially symmetry properties are used. In order to list all convex figures, two variants are included.